A variety of economic, social and technological changes in recent years have prompted intense interest in reliable and dense storage systems. The Internet requires companies to set up web and commerce servers which require storage systems. Editing and storage of media such as video call for large amounts of storage from which it is desired to retrieve arbitrary portions without undue delay. It is desirable for these systems to be rack-mountable in standardized 19-inch racks. These and other applications have led to the development of storage systems made up of large numbers of hard disk drives. In such a system it is desired that each drive be individually removable and replaceable. This generally leads to a system having an enclosure or shelf with a dozen or more slots into which disk drive carriers may slide. Each carrier has a bezel and handle assembly which is visible when the carrier has been inserted into the enclosure. The bezel serves a number of important functions, including providing a uniform appearance of the system when its slots are fully populated with carriers. The handle is used to assist in extraction of the carrier and to assist in insertion of the carrier.
Balanced against ease of removal and replacement, however, is the concern that a drive carrier should not be at risk of inadvertent removal, and that it should not be disposed to vibrate loose from its operating position. It is thus necessary to devise a locking system that locks each carrier into place except in the rare instances in which it is desired that a carrier be capable of being removed. Each carrier must be individually capable of being locked or unlocked, separately from any other carrier.
Yet another design constraint is that it is desired to fit as many drives (and carriers) as possible into an enclosure, and to minimize the number of xe2x80x9crack unitsxe2x80x9d (units of vertical spacing of 1.75 inches) taken up by the enclosure. This makes the front-panel area of the enclosure (chiefly the bezel and handle portions) valuable and scarce. Some prior-art locking arrangements have symbols indicative of the locked and unlocked conditions, which take up valuable space and may not be easy to distinguish in suboptimal viewing conditions.
Experience shows that damage can occur to a carrier, to the enclosure, or to both, in instances in which a user tries to remove a carrier that is locked. Under the best of circumstances it may not be easy to distinguish between the locked and unlocked configurations of a carrier. Some rack-mounted systems, however, are behind perforated doors, Lexan doors, or other obstructions. Some prior-art mechanisms which are intended to provide an indication of the locked or unlocked status of a carrier are mechanically complicated, do not provide unambiguous indications, or have features which take up valuable space in the bezel/handle assembly.
It is thus desirable to have a locking mechanism and related system which is mechanically simple, which provides unambiguous indication of the locked or unlocked status of each carrier, and which do not take up valuable space in the bezel/handle assembly.
In a disk drive enclosure system having carriers fitting into slots in the enclosure, each carrier has a lock mechanism. The lock mechanism has a part which rotates between locked and unlocked positions, and the part has a feature that blocks removal of the carrier when the part is in the locked position, while permitting removal of the carrier when the part is in the unlocked position. The part is plastic and is molded of a clear material serving as a light pipe. A light source is behind the part, so that the ability of light to pass through the part is affected by the locked/unlocked position of the part. The part has a shape feature that assists a user in distinguishing between locked and unlocked positions, and the light indicator further assists the user in this way. Valuable bezel space is saved, especially in comparison with some prior-art locking mechanisms.